|
|
@ -1,38 +1,26 @@ |
|
|
|
----- [[ AXIAL/CUBE COORDINATE SYSTEM FOR AMULET/LUA]] ------------------------- |
|
|
|
--[[ author@churchianity.ca |
|
|
|
-- INTRODUCTION |
|
|
|
this is a library for making grids of hexagons using lua. |
|
|
|
it has made exclusive (though not thorough) use of standard lua |
|
|
|
5.2 functionality, making it as portable as possible. it |
|
|
|
doesn't even use a point class, simply returning tables |
|
|
|
of integers, which can later be unpacked into your amulet |
|
|
|
vectors, or whatever else you want to use. in honor of amulet, |
|
|
|
when necessary to name cube/hex coordinates, (s, t, z) is the |
|
|
|
convention. |
|
|
|
|
|
|
|
only returning tables can result in some nasty looking lines |
|
|
|
with lots of table unpacks, but if your graphics library likes |
|
|
|
traditional lua types, you will be better off. |
|
|
|
|
|
|
|
it supports triangular, hexagonal, rectangular, and |
|
|
|
parallelogram map shapes. |
|
|
|
this is a hexagonal grid library for amulet/lua. |
|
|
|
it uses axial coordinates or cube/hex coordinates when necessary. |
|
|
|
by amulet convention, hexes are either vec2(s, t) or vec3(s, t, z) |
|
|
|
but nearly always the former. |
|
|
|
|
|
|
|
it supports non-regular hexagons, though it's trickier to get |
|
|
|
working in amulet. TODO work on this. |
|
|
|
|
|
|
|
-- NOTE ON ORIENTATION + AMULET |
|
|
|
because of the way amulet draws hexagons (amulet essentially |
|
|
|
draws a 6-sided circle from a centerpoint, instead of of a |
|
|
|
series of lines connecting points), the flat orientation is |
|
|
|
default and recommended. other orientations are possible |
|
|
|
with am.rotate, but can cause aliasing issues. TODO work on this. |
|
|
|
-- TODO NOTE - |
|
|
|
amulet has another draw function I neglected, simply am.draw. |
|
|
|
i don't understand how it works, but it seems to be able to |
|
|
|
draw arbitrary polygons via a list of vertices. so. |
|
|
|
in some rare cases, coordinates will be passed individually, usually |
|
|
|
because they are only passed internally and should never be adjusted |
|
|
|
directly. |
|
|
|
|
|
|
|
in amulet, vector arithmetic already works via: + - * / |
|
|
|
additional things such as equality, and distance are implemented here. |
|
|
|
|
|
|
|
+support for parallelogram, triangular, hexagonal and rectangular maps. |
|
|
|
+support for simple irregular hexagons (horizontal and vertical stretching). |
|
|
|
|
|
|
|
classes are used sparsely. maps implement a few constructors, for storing |
|
|
|
your maps elsewhere. |
|
|
|
|
|
|
|
-- RESOURCES USED TO DEVELOP THIS LIBRARY |
|
|
|
https://redblobgames.com/grid/hexagons - simply amazing. amit is a god. |
|
|
|
https://redblobgames.com/grid/hexagons - simply amazing. |
|
|
|
http://amulet.xyz/doc - amulet documentation |
|
|
|
TODO that place that had the inner circle/outer circle ratio?? |
|
|
|
|
|
|
@ -41,23 +29,23 @@ |
|
|
|
----- [[ GENERALLY USEFUL FUNCTIONS ]] ----------------------------------------- |
|
|
|
|
|
|
|
-- just incase you don't already have a rounding function. |
|
|
|
function round(n) |
|
|
|
local function round(n) |
|
|
|
return n % 1 >= 0.5 and math.ceil(n) or math.floor(n) |
|
|
|
end |
|
|
|
|
|
|
|
---- [[ HEX CONSTANTS ]] ------------------------------------------------------- |
|
|
|
|
|
|
|
-- all possible vector directions from a given hex by edge |
|
|
|
HEX_DIRECTIONS = {{ 1 , 0}, |
|
|
|
{ 1 , -1}, |
|
|
|
{ 0 , -1}, |
|
|
|
{-1 , 0}, |
|
|
|
{-1 , 1}, |
|
|
|
{ 0 , 1}} |
|
|
|
local HEX_DIRECTIONS = {vec2( 1 , 0), |
|
|
|
vec2( 1 , -1), |
|
|
|
vec2( 0 , -1), |
|
|
|
vec2(-1 , 0), |
|
|
|
vec2(-1 , 1), |
|
|
|
vec2( 0 , 1)} |
|
|
|
|
|
|
|
-- HEX UTILITY FUNCTIONS ------------------------------------------------------- |
|
|
|
|
|
|
|
function hex_round(s, t) |
|
|
|
local function hex_round(s, t) |
|
|
|
rs = round(s) |
|
|
|
rt = round(t) |
|
|
|
rz = round(-s - t) |
|
|
@ -74,7 +62,7 @@ function hex_round(s, t) |
|
|
|
rz = -rs - rt |
|
|
|
end |
|
|
|
|
|
|
|
return {rs, rt} |
|
|
|
return vec2(rs, rt) |
|
|
|
end |
|
|
|
|
|
|
|
----- [[ LAYOUT, ORIENTATION & COORDINATE CONVERSION ]] ----------------------- |
|
|
@ -89,30 +77,29 @@ local POINTY = {3.0^0.5, 3.0^0.5/2.0, 0.0, 3.0/2.0, |
|
|
|
|
|
|
|
-- layout. |
|
|
|
function layout_init(origin, size, orientation) |
|
|
|
return {origin = origin or {0, 0}, |
|
|
|
size = size or {11, 11}, |
|
|
|
return {origin = origin or vec2(0), |
|
|
|
size = size or vec2(11), |
|
|
|
orientation = orientation or FLAT} |
|
|
|
end |
|
|
|
|
|
|
|
-- hex to screen |
|
|
|
function hex_to_pixel(s, t, layout) |
|
|
|
function hex_to_pixel(hex, layout) |
|
|
|
M = layout.orientation |
|
|
|
|
|
|
|
x = (M[1] * s + M[2] * t) * layout.size[1] |
|
|
|
y = (M[3] * s + M[4] * t) * layout.size[2] |
|
|
|
x = (M[1] * hex.s + M[2] * hex.t) * layout.size.x |
|
|
|
y = (M[3] * hex.s + M[4] * hex.t) * layout.size.y |
|
|
|
|
|
|
|
return {x + layout.origin[1], y + layout.origin[2]} |
|
|
|
return vec2(x + layout.origin.x, y + layout.origin.y) |
|
|
|
end |
|
|
|
|
|
|
|
-- screen to hex |
|
|
|
function pixel_to_hex(x, y, layout) |
|
|
|
function pixel_to_hex(pix, layout) |
|
|
|
M = layout.orientation |
|
|
|
|
|
|
|
px = {(x - layout.origin[1]) / layout.size[1], |
|
|
|
(y - layout.origin[2]) / layout.size[2]} |
|
|
|
pix = (pix - layout.origin) / layout.size |
|
|
|
|
|
|
|
s = M[5] * px[1] + M[6] * px[2] |
|
|
|
t = M[7] * px[1] + M[8] * px[2] |
|
|
|
s = M[5] * pix.x + M[6] * pix.y |
|
|
|
t = M[7] * pix.x + M[8] * pix.y |
|
|
|
|
|
|
|
return hex_round(s, t) |
|
|
|
end |
|
|
@ -129,12 +116,12 @@ end |
|
|
|
function map_parallelogram_init(layout, width, height) |
|
|
|
map = {} |
|
|
|
setmetatable(map, {__index={layout=layout, |
|
|
|
shape="parallelogram", |
|
|
|
width=width, |
|
|
|
height=height}}) |
|
|
|
width=width, |
|
|
|
height=height, |
|
|
|
shape="parallelogram"}}) |
|
|
|
for s = 0, width do |
|
|
|
for t = 0, height do |
|
|
|
table.insert(map, hex_to_pixel(s, t, layout)) |
|
|
|
table.insert(map, hex_to_pixel(vec2(s, t), layout)) |
|
|
|
end |
|
|
|
end |
|
|
|
return map |
|
|
@ -144,11 +131,11 @@ end |
|
|
|
function map_triangular_init(layout, size) |
|
|
|
map = {} |
|
|
|
setmetatable(map, {__index={layout=layout, |
|
|
|
shape="triangular", |
|
|
|
size=size}}) |
|
|
|
size=size, |
|
|
|
shape="triangular"}}) |
|
|
|
for s = 0, size do |
|
|
|
for t = size - s, size do |
|
|
|
table.insert(map, hex_to_pixel(s, t, layout)) |
|
|
|
table.insert(map, hex_to_pixel(vec2(s, t), layout)) |
|
|
|
end |
|
|
|
end |
|
|
|
return map |
|
|
@ -158,14 +145,14 @@ end |
|
|
|
function map_hexagonal_init(layout, radius) |
|
|
|
map = {} |
|
|
|
setmetatable(map, {__index={layout=layout, |
|
|
|
shape="hexagonal", |
|
|
|
radius=radius}}) |
|
|
|
radius=radius, |
|
|
|
shape="hexagonal"}}) |
|
|
|
for s = -radius, radius do |
|
|
|
t1 = math.max(-radius, -s - radius) |
|
|
|
t2 = math.min(radius, -s + radius) |
|
|
|
|
|
|
|
for t = t1, t2 do |
|
|
|
table.insert(map, hex_to_pixel(s, t, layout)) |
|
|
|
table.insert(map, hex_to_pixel(vec2(s, t), layout)) |
|
|
|
end |
|
|
|
end |
|
|
|
return map |
|
|
@ -174,49 +161,28 @@ end |
|
|
|
-- returns rectangular map. |
|
|
|
function map_rectangular_init(layout, width, height) |
|
|
|
map = {} |
|
|
|
setmetatable(map, {__index={layout=layout, |
|
|
|
shape="rectangular", |
|
|
|
width=width, |
|
|
|
height=height}}) |
|
|
|
mt = {__index = {layout = layout, width = width, height = height, |
|
|
|
|
|
|
|
retrieve = function(pix) |
|
|
|
hex = pixel_to_hex(pix, layout) |
|
|
|
print(tostring(hex)) |
|
|
|
print(map[tostring(hex)]) |
|
|
|
return vec2(hex.s, hex.t + math.floor(hex.s / 2)) |
|
|
|
end, |
|
|
|
|
|
|
|
store = function(hex) |
|
|
|
pix = hex_to_pixel(hex, layout) |
|
|
|
return vec2(pix.x - math.floor(pix.y / 2), pix.y) |
|
|
|
end}} |
|
|
|
|
|
|
|
for s = 0, width do |
|
|
|
soffset = math.floor(s/2) |
|
|
|
|
|
|
|
for t = -soffset, height - soffset do |
|
|
|
table.insert(map, hex_to_pixel(s, t, layout)) |
|
|
|
end |
|
|
|
end |
|
|
|
return map |
|
|
|
end |
|
|
|
|
|
|
|
-- places single hex into map table, if it is not already present. |
|
|
|
function map_store(map) |
|
|
|
|
|
|
|
end |
|
|
|
|
|
|
|
-- retrieves single hex from map table. explodes if can't find it. |
|
|
|
function map_retrieve(map, hex) |
|
|
|
if map.shape == "rectangular" then |
|
|
|
if map.layout.orientation == FLAT then |
|
|
|
return {hex[1] + math.floor(hex[2]/2), hex[2]} |
|
|
|
else |
|
|
|
return {hex[1], hex[2] + math.floor(hex[1]/2)} |
|
|
|
end |
|
|
|
elseif map.shape == "hexagonal" then |
|
|
|
if map.layout.orientation == FLAT then |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
map[tostring(vec2(s, t))] = hex_to_pixel(vec2(s, t), layout) |
|
|
|
end |
|
|
|
elseif map.shape == "parallelogram" then |
|
|
|
if map.layout.orientation == FLAT then |
|
|
|
|
|
|
|
else |
|
|
|
|
|
|
|
end |
|
|
|
else |
|
|
|
|
|
|
|
end |
|
|
|
|
|
|
|
|
|
|
|
setmetatable(map, mt) |
|
|
|
return map |
|
|
|
end |
|
|
|
|